Pneumatic compaction of asphalt compositions



R. L. FERM ETAL Filed Aug. 15, 1965 INVENTORS RICHARD L. PERM ROBCRT J.SCHMIDT ATTORNEYS 1967 R. L. FERM ETAL 3,344,721

PNEUMATIC COMPACTION OF ASPHALT COMPOSITIONS Filed Aug. 13. 1965 2Sheets-Sheet INVENTORS- RICHARD L. FEPM ROBERT J. SCHMIDT 6. 42. ATTORNEYS United States Patent 3,344,721 PNEUMATIC COMPACTION 0F ASPHALTCOMPOSITIONS Richard L. Ferm and Robert J. Schmidt, El Cerrito, Califi,assignors to Chevron Research Company, San Francisco, Califi, acorporation of Delaware Filed Aug. 13, 1965, Ser. No. 479,521 7 Claims.(CI. 94-22) ABSTRACT OF THE DISCLOSURE A method and apparatus forpneumatically compacting asphalt concrete at temperatures of the asphaltconcrete composition in excess of 180 R, which comprises spraying ontothe rubber pneumatic compacting wheels a dilute unstable oil-in-wateremulsion.

This invention concerns a novel method for compacting and rollingasphaltic composition roadbeds, the compositions used therein and anapparatus which employs the method of this invention particularlyadvantageously.

A common material used for paving is asphalt concrete. Asphalt concreteis primarily a mixture of rock aggregate of varying size bound togetherby a bituminous binder. When paving the asphalt concrete, it isnecessary to compact the composition to remove most of the air pocketstrapped in the composition. These air pockets are referred to as voids.It is generally believed that from about 4 to percent voids provides themost desirable properties for a pavement. This degree of voids issufficiently low to minimize aging and weathering of the asphalt, whilestill permitting the desirable mechanical properties of rock-to-rockcontact in the roadway.

In order to obtain the low degree of voids, it is necessary toefficiently compact the asphalt concrete composition laid down.Satisfactory compaction is best achieved with pneumatic compactors, butin order for pneumatic compactors to be eflicient, the asphalt concretecomposition must have a reasonable dergree of fluidity. Best compactionresults are therefore achieved with the asphalt concrete at relativelyhigh temperatures, temperatures above 180 F. and generally of about 225to 300 F. At lower temperatures, the asphalt concrete composition is notfluid enough to permit eflicient compaction.

Unfortunately at temperatures above 180 F., the asphalt binder sticks tothe pneumatic tires, tearing up the road and creating irregularities.Therefore, in the past it has been necessary to compact the roadbed atrelatively low temperatures at which compaction by pneumatic tires isinefficient and becomes relatively expensive because repeated rollingsare necessary.

Pursuant to this invention, a dilute moderately unstable oil-in-wateremulsion is sprayed onto the pneumatic compactors while rolling theasphalt concrete pavement at temperatures above 180 F., preventing thesticking and adhering of the asphalt concrete to the pneumatic tires. Incombination with this method is an apparatus which employs pneumatictires forwardly to compact the asphalt concrete composition and a steelroller rearwardly to smooth out the compacted roadway and add a furtherdegree of compaction.

The method of this invention can be used with any pneumatic compactorand as indicated is particularly advantageous at relatively hightemperatures, i.e., above 180 F. By combining the present method with anapparatus which combines pneumatic tires as pneumatic compactors and asteel roller, an apparatus is provided which can efliciently and easilybe used on relatively small jobs or jobs requiring an apparatus witheasy mobility and maneuverability. The apparatus is described in theaccompanying drawings.

Patented Oct. 3, 1967 FIG. 1 is a side elevational view of the pneumaticcompactor and roller of this invention;

FIG. 2 is a partial plan view omitting numerous parts in the interest ofclearness, and indicating the yoke in two different turned positions;

FIG. 3 is a partial plan view looking downward on the forward portion ofthe apparatus;

FIG. 4 is a front elevation view.

The combined pneumatic compactor and road roller vehicle of ourinvention comprises a main frame part, part of which is seen as alongitudinally extending side member 1 and platform support 2,supporting the forward portion of the frame, a plurality of pneumatictires 3 mounted in a yoke pivotably connected to said frame, an emulsionapplicator to maintain a thin film of dilute oil-in-water emulsion onthe face of the pneumatic tires, and a steel driving roller 4 powered toprovide propulsion for the vehicle supporting the rear portion of saidframe.

The portion of the frame comprising the longitudinally extending sidemember 1 is supported in the rear through struts 6 connected to thebearing 7 in which the steel roller axle 8 is journaled. The steelroller or rear axle 8 is rigidly connected to the steel drive roller 4which engages the roadway. A cover 9 is provided for the steel roller. Adiesel engine 11 is mounted on the frame and operatively connected tothe steel roller 4 (the particular means not being represented)providing the propulsion means for the vehicle.

Forwardly of the frame is a platform 12 upon which is mounted a driverseat 13, various pedals 14a and 14b and a lever 16 for controlling themovement of the vehicle, as well as a tiller wheel operably connected tothe yoke 19 (the connecting means is not represented) to turn the yoke,which provides the means for maneuvering the vehicle.

Pivotally mounted in the forward section of the frame platform 12 is avertical shaft 18 rigidly connected to the center of the yoke 19.Pneumatic tires 3, engaging the roadway, are rigidly mounted on a frontaxle 21 relatively evenly spaced about one tire width apart. The axle 21is rotatably mounted in the yoke. Connected to the yoke 19 is anauxiliary frame 22 positioned above the pneumatic tires.

' To spray the dilute oil-in-water emulsion on the pneumatic tires 3,the emulsion reservoir 23 mounted on the auxiliary frame 22 is filedthrough an upper port 24 with the emulsion. The exit valve 26 and thevalve 27 between the emulsion reservoir 23 and the pressure reservoir 28are closed and the pressure reservoir 28 is then pressurized through theopen gas intake valve 29. When the pressure reservoir 28 is filled, theintake valve 29 is closed, the valve between the reservoirs 27 is openedand the gas is fed into the emulsion reservoir 23 through the connectingconduit 31 applying pressure against the emulsion.

An open-close valve 32 is provided near the driver and the lever control33 is pictured in the normally open position. The dotted lines 33aindicate the closed position. The reservoir exit valve 26 is opened andthe pressure of the emulsion set with the diaphragm valve 36, readingthe pressure on the gauge 37.

When the vehicle is ready to move, the driver moves the lever control 33to the open position and the emulsion then flows through the conduit 38to the open-close valve 32 and then through a second conduit 39 to thefitting 40 which is connected to the rigidly mounted manifold 41.

A plurality of nozzles 42 equal to the number of tires is mounted in themanifold and positioned above theframe 22 is a bar 44 onwhich aremounted mats or -acrossthe face of the tires and remove fortuitous minorbits of asphalt and aggregate which may have adhered to the tires 3.Springs 47 are positioned at opposite ends of theauxiliary frame 22connected from the auxiliary frame 22 to connecting members 43 andmaintain a mild tension on the bar 44 to keep the wipers 46 in contactwith the faces of the tires 3. The wipers 46 may be moved out ofengagement with the tire face, by disengaging the springs 47 and raisingthe bar 44 pivoting .around the connection to the frame 22.Thusreplacement or repair of the wipers may be easily performed.

The steering mechanism for the vehicle (except for the steering wheeland shaft, this mechanism is not represented) turns the yoke 19 in thedirection the vehicle is to go. In FIG. 2, the position of the yoke 19when turning to the left is indicated by the solid lines, to the rightby the broken lines. As the yoke turns, the conduits 38 and 39 areextended or retracted. A telescoping device is provided to support theconduits and take up any slack. Mounted on the platform 12 is a tubularmember 48', a second shaft 49 is fitted telescopically with the tubularmember. A spring 51 extends from the lip of the tubular member 48 to anarm 52, the arm 52 being rigidly connected at one end to the shaft 49,and has sufiicient tension to maintain the shaft 49 in the extendedposition when the weight of the filled conduits 38 and 39 is pressingdown on the arm 52, but contracts when additional pressure is applied byextending the conduits. The shaft 49 is slotted in the tubular member 48to prevent rotation. A shoulder 53 is provided on the end of the arm 52opposite the end'connected to the shaft 49 to prevent the conduits fromslipping off.

The vehicle will generally have a total weight from about'0.25 to tons,usually about 1 to 5 tons. The pneumatic tires will generally havediameters of from about 24 to 48" and face widths of about 4 to 16'. Thedistance from the outermost edges of the most distant tires will beslightly less than the width of the steel roller. The pressure in thetires will usually vary from about 20 p.s.i. or 120 p.s.i. with theloading per tire being in the range of about 500 to 1,000 lbs.; about 4to 6 tires will be used. The tires normally be from about /2 to thediameter of the steel roller.

' The steel roller will vary from about 18 to 66" in diameter and about30 to 34" wide. The loading will be about 100 lbs. to 600 lbs. perlineal inch.

The apparatus of this invention which employs front pneumatic tires forcompaction sprayed with the antisticking emulsions of this invention anda rear steel roller permits the manufacture and use of relatively lightweight machines which are extremely mobile and can be used for jobswhich are either relatively small or require a significant degree ofmaneuverability. The great efiiciency in obtaining improved roadways orasphalt concrete composition pavements by obtaining the desired degreeof compaction and percentage of voids is possible because the pneumatictires are able to operate at relatively high temperatures at whichsatisfactory compaction is achieved and the steel roller furtherenhances the compaction and smooths out the pavement. Thus with onemanuverable vehicle of relatively low weight, high compaction isachieved and a smooth, dense, long-wearing surface is obtained.Heretofore, for small jobs or in those situations Where only smallapparatuses could be used, compaction was not efficiently done and onlyrelatively short-lived pavements could be obtained.

Moreover, it was previously found that with asphaltconcrete pavements athigh temperatures, i.e., above 180 F the steel roller created a Wave infront of the roller in the direction of travel. Rather than compactingthe surface, decompaction occurred. In the subject apparatus, with thepneumatic tires initially compacting the asphalt- 4 concrete pavement,the weight of the vehicle is distributed over a much wider area thanwith a steel roller, avoiding decompaction and providing goodcompaction; the steel roller then serves to roll the surface smooth withfurther enhancement of the compaction.

While the dilute aqueous oil-in-Water emulsions of this invention findparticular advantage with the aforedescribed apparatus, the emulsions ofthis inventioncan be used with any road rolling'apparatusemployingpneumatic tires or in fact in any situation where hot asphalt comes incontact with rubber or similar material and the hot asphalt then has tobe removed from the rubber, e.g., rubber conveyors in hot asphalt mixplants.

While in the above apparatus, spraying was used in applying theemulsionspraying is found to be the most eflicient way of applying theemulsion, particularly as.

measured by the amount of material expendedany other means may also beused which provides a continuous even flow of the emulsion to thepneumatic tire face. Gravity flow is satisfactory, trickling theemulsion onto the pneumatic tire face, except when the apparatus isoperating on an incline; in this situation, the tires on the upwardportion of the incline are not likely to receive any of the emulsion.Numerous devices have been patented for feeding liquids evenly oversteel rollers and these can gen erally be adapted to be used withpneumatic tires to provide a continual even stream of emulsion onto thetire faces.

In order to insure an even distribution of the emulsion on the pneumatictire face, generally, some type of wiper will be used. The wiper alsoserves to remove any small bits of adventitious asphalt or aggregatewhich may have stuck to the tire face. Most commonly, a mat or coco matwill be used and these have found extensive employment, particularlywith the very inefficient use of water to prevent sticking of theasphalt binder to the pneumatic tires. 7 The aqueous emulsion will becontinuously applied to the pneumatic tires face as the compactingapparatus rides over the hot asphalt concrete surface. The amount of theemulsion which is applied is not critical to this invention, dependingon a variety of variables: field conditions, the particular emulsionused, the temperature at which pneumatic compaction is occurring, etc.Generally, about 1 gallon per hour per pneumatic tire will be used, andusually, less than 15 gallons per hour per tire will be required whenthe apparatus is in continuous use. Frequently, from about 3 to 8gallons per hour per tire will sufiice. However, the particular rate ofapplication can be readily determined in the field by observing theminimum rate required to minimize or avoid the adherence of the asphaltbinder.

The emulsions of this invention can be used with various asphaltcontaining paving compositions. The emulsions are particularly usefulwith asphalt concrete, especially when the asphalt concrete ispneumatically compacted at temperatures above F., usually from about 200F. to 300 F. In those instances where sticking is a problem with steelrollers, the emulsions used in this invention may also find use. hisalso found that with asphalts containing polymeric additives, e.g.,rubber, asphalt sticking becomes a problem which can be alleviated bythe application of the emulsions described inthis invention to eitherthe rubber or steel rollers or both. Therefore, while the emulsions ofthis invention find particular use with asphalt concrete at elevatedtemperatures, they may also be used with advantage when paving asphaltcompositions under a variety of other conditions. As already indicated,other uses for the emulsions can also be readily found when asphaltadherence to rubber or similar material becomes a significant problem.

The dilute oil-in-water emulsion of this invention is' comprised ofwater, a hydrocarbonaceous liquid, referred to as oil, and anemulsifier. Other additives may also be included as desired or needed.The oil will generally be present in amount of at least about 0.5 weightpercent any may be as high as 20 weight percent, usually not more thanweight percent, depending on the desired use. For use with asphaltconcrete paving, the composition usually will have from about 1 to 5weight percent of oil. The emulsifier will be present in from about 0.1to weight percent based on the oil, preferably from about 0.5 to 5weight percent based on the oil. The remainder of the composition iswater and other additives. The water, therefore, will be present in anamount of from 85 to 99 weight percent, more usually 90 to 99 weightpercent based on the amount of oil and other additives.

Initially, the oil-in-water emulsion may be prepared as a concentrateand diluted prior to use. The concentrates will have from about 50 to 75weight percent of oil.

The oil or hydrocarbonaceous liquid as a practical matter will have aboiling point of at least about 200 F. The boiling point is one ofconvenience based on a minimum volatility in order to permit sufi'icientoil to remain on the hot pneumatic tire and yet sufficient volatilitythat, at least slowly, the oil will evaporate from the surface of thepavement. Too great a volatility will require large amounts of thehydrocarbonaceous fluid, while too low a volatility will permit the oilto remain for an indefinite time in the pavement resulting in thesoftening of the pavement. While this is not a serious problem in viewof the very dilute character of the emulsion, in instances where theoperator of the roller, while the roller is standing still, allows theemulsion to continue to run for a long period of time, large puddles mayform and appreciable amounts of oil may be absorbed by the pavement.However, this is anticipating an extreme situation which generally neednot govern the type of oil used.

In most instances, the maximum boiling point will be below about 1,000"F., more usually below about 850 F. Preferably, the boiling point rangewill be from about 300 to 850 F. That is, any hydrocarbonaceous fluidused would have at least about 50 weight percent of the mixture boilingin the indicated range.

Preferably, the hydrocarbonaceous liqiud or oil will not be too viscous.By too viscous is meant a viscosity at 210 F. of greater than about 100seconds, Saybolt Universal (SSU). Preferably, the oil will have aviscosity of less than about 60 SSU at 210 F.

The oil may be either aliphatic, aromatic, alicyclic or combinationsthereof. While any of these hydrocarbon types are useful for preventingsticking of the asphalt to the pneumatic roller, it is found thataromatic hydrocarbons attack the rubber and reduce the useful life ofthe pneumatic rubber roller. To that extent, hydrocarbons free ofaromatic unsaturation, particularly paraflinic hydrocarbons arepreferred. By paraflinic hydrocarbons is intended predominantlyparaflinic and is not intended to exclude mixtures which contain minoramounts of aromatic hydrocarbons.

Illustrative hydrocarbons which are readily avilable are diesel fuels:broad range, heavy and light, boiling, respectively, in the range of325650 F., 550650 F., and 325 550 F., pale oils, neutral oils, thinners,particularly parafliinic thinners, etc. As evidenced by the aboveexamples, for the most part, mixtures of hydrocarbons will be usedbecause they are inexpensive and readily available.

The emulsifiers which are used may be anionic, cationic or nonionic. Theemulsifiers are described in Kirk-Othmer, Encyclopedia of ChemicalTechnology, volume 5, Interscience Encyclopedia Incorporated, New York(1950), page 701 if. While the emulsifiers used in this invention may beof any type, i.e., anionic, cationic or nonionic, it is necessary thatin any partition between water and oil (hydrocarbon liquid), theemulsifier be predominantly soluble in the water. That is, more of theemulsifier will be dissolved in the water thanin the oil. Theemulsifiers fulfilling this requirement will be referred to ashydrophilic.

The partition can be readily determined by shaking a sample of theemulsifier with equal volumes of water and oil, separating the resultingphases and analyzing the concentration of emulsifier in each phase.

The various emulsifiers may be used in individually or in combination.Of course, an anionic emulsifier may not be used with a cationicemulsifier. Illustrative of various emulsifiers are polyoxyethylenesorbitan monopalmitate,

tallow trimethyl ammonium chloride, alkyl alkylamino imidazolines,etho-xylated and polyethoxylated dodecanyl phenol, acid salts of tallow1,3-propylene diamine, polyethoxylated quaternary ammonium halides,polyethoxylated fatty amines and their salts, alkylbenzene s-ulfonatealkali metal salts, etc. The preferred emulsifiers are the cationicemulsifiers such as the alkyl ammonium salts.

Generally, the emulsion is prepared as a concentrate having from about50 to 75 weight percent oil and from 0.1 to 15 weight percent ofemulsifier based on the weight of oil, usually 0.5 to 5 weight percent.The amount of emulsifier will be governed by the stability of theemulsion. The emulsifier concentration should provide an emulsion ofonly limited stability. That is, the emulsion on being sprayed onto thetires collapses and provides a protective film on the tire face.

The emulsion is prepared by mixing its various constituents under highshear, conditions, e.g., a colloid mill. Other methods include the useof Charlotte mills, centrifugal pumps, Manton-Gaulin homogenizer orpaint mills. Methods of preparing emulsions by using high shearconditions are well known in the art and do not require extensiveexemplification here. The particular apparatus which is used to providethe high shear conditions is not critical to this invention. For themost part, the hydrocarbonaceous particles will be less than about 6,u.median diameter, preferably 4n median diameter.

Other additives may also be included in the emulsion. Additives includeemulsion stabilizers, e.g., carboxymethyl cellulose, odorant to maskoffensive odors, e.g., new mown hay, Deodall brand deodorants, etc. Theamount of the individual additives will generally range from about 0.01to 0.5 weight percent of the total composition.

As already indicated, the emulsions may be used with any pneumaticcompacting device. The pneumatic rollers or tires may be mounted onself-propelled vehicles by themselves or in combination with steelrollers or on trailers. The size of the tires will generally be fromabout 24" to 72" in diameter and from about 5" to 15" in Width. Forcompacting the relatively soft surface of bituminous compositions attemperatures above 180 F., the tires will be pressurized to about 20 top.s.i. and provide a pressure against the pavement surface of from about20 to 120 lbs/sq. in. The loading per tire will vary from about 500 to2,000 lbs.

In order to demonstrate the effectiveness of the dilute oil-in-wateremulsions, a 5 ton Bros pneumatic roller was used. This roller wasequipped with 9 wheels in all, 5 on one end and 4 on the other. Thetires were 30" in diameter, 8 in width and pressurized to 40 p.s.i. Themodified pneumatic roller used for this work had a weight of 10,370 lbs,giving an average of 1,152 lbs. on each of the 9 tires.

The vehicle was equipped with a spray system that permitted 5 differentmaterials to be individually applied simultaneously to either a singleor a pair of the tires. Five individual small blow cases (approximately8.5 gallons each) were pressured through a reducing valve from anitrogen cylinder. Each of the materials being tested was lead from therespective blow case through tubing to small spray nozzles positioned tospray fully across the face of each tire at a rate of 3 gallons per hourper tire. Individually spring loaded coco mats wiped each tire. Thesemats were adjustable and could be raised out of contact with the tire ifdesired.

Various emulsions were prepared by varying the hydrocarbonaceous fluidand emulsifier. The different emulsions were introduced into the blowcases and applied to the 7 pneumatic rollers. The following tableindicates the compositions of the various emulsions, the maximumtemperature of rolling attempted without significant adherence to thepneumatic tires, whether coco mats were used, and compares these resultswith those obtained with other materials.

Emulsions coming within the scope vof this invention were subjected tofurther vigorous testing. Using the equip ment and method describedabove under exteremely hot climactic conditions, various emulsions weretested up to 250 F. for preventing adherence to the pneumatic tires.Table II indicates the emulsions tested with success.

TABLE I Maximum Temperature of Rolling, F.

Hydrocarbon 1 Weight Emulsifier 3 Weight 7 Percent 3 Percent 4Intermittent Sustained Intermittent Without With With Coco Mats CocoMats 0000 Mats Tall oil acid triethanol amine salt.

Nalcamine G39M Span 40 Tween 40 Span 40- Arquad T. Arquad T. Arquad T lA--Diesel fuel; boiling range, 350675 F.; Vmu=4l0 SSU (Vmn=Viscosity at100 F.) (Seconds, Saybolt Universal). B-Predomlnantly aliphatic thinner;boiling range,

314-396 F.; Vioo=1.05 cs. (centistokes).

C-Predominantly aromatic thinner; boiling range, 360414 F.; Vioo=1.05cs.

D-Predorninantly aliphatic thinner; boiling range, 318389I'D-Predominantly aliphatic thinner; boiling range, 346392 F-Pale oil;Viuo=l001l0 SSU. G-Neutral oil; V 0o=43O SSU.

2 Weight percent hydrocarbon fluid in final emulsion as diluted for usein pneumatic r0ller. 3 Nalcamine G39M-Imidazoline product from tall oiland diethylene triamine, hydrochloride salt.

Arquad TTallowtrimethylammoninm chloride. F 38C opolymer of ethylene andpropylene oxides. NlweEthoxylated dodecenylphenol ABS-Allrylbenzenesulfonic acid (alliyl of from 12-15 carbon atoms), potassium salt.

Span 40-Sorbitan monopalmltate. Tween 40Polyoxyethylene sorbitanmonopalmitate.

5 Size and temperature tablished.

TABLE II.EMULSIO-N COMPOSITION Emulsifier 1 used with Weight percentweight percent diesel fuel: 2 0

UILALQNHLII (Pilot (Union Carbide, Chemicals t percent of hydrocarbon.(1 maximum temperature to be es- Tests were also made as previouslydescribed, varying the amount of emulsifier and diesel fuel to determinethe effect of varying concentration on preventing asphalt adherence. Therolling was performed at 250260 F. and the following Table III indicatescompositions which were found to be effective. TABLE III.ANTISTICKINGEMULSION COMPOSITIONS Weight Percent Weight Percent Cellosize 1 DieselFuel Arquad T-50 QP 15000 Stabilizer (form of hydroxyethyl cellulose)supplied by Union Carblde and Chemicals 00.

It is evident from the above table that by use of the process of thisinvention employing the disclosed emulsions, numerous advantages areobtained in the pneumatic compacting of asphalt concrete as well asother asphalt containing paving compositions. Particularly, superiorcompaction is obtainable because compaction may be carried out at highertemperatures, permitting optimization of the desirably low percentage ofvoids. Furthermore, the rolling may more closely follow the laying ofthe asphalt concrete, since rolling need not await cooling of theasphalt concrete to a temperature at which sticking will not occur inthe absence of the emulsions disclosed in this invention. Furthermore,the aqueous emulsions provide an inexpensive and efiicient way tooperate pneumatic compaction at elevated temperatures to providesuperior pavements.

The apparatus of this invention provides a maneuverable, relativelylight weight compacting and rolling vehicle which provides the desiredcompaction for durable, long-lived asphalt-concrete pavements.

As will be evident to those skilled in the art, various modifications onthis invention can be made or followed, in the light of the foregoingdisclosure and discussion, without departing from the spirit or scope ofthe disclosure or from the scope of the following claims.

We claim:

1. A method for efliciently compacting and rolling bituminous pavementcompositions at temperatures in excess of 180 E, which comprisescompacting the pavement with a plurality of pneumatic tires whilespraying onto the faces of said pneumatic tires at a sufiicient rate toprevent adhesion of the bituminous pavement composition to saidpneumatic tires an oil-in-water emulsion comprising from 0.5 to 10Weight percent of a hydrocarbonaeeous fluid boiling in the range ofabout 200 F. to 1000 F. and having a viscosity at 210 F. of less thanabout 100 SSU, from 0.1 to 15 weight percent based on the weight of saidhydrocarbonaceous fluid of a hydrophilic emulsifier and water.

2. A method according to claim 1 wherein said hydrocarbonaceous fluid ispresent in an amount of from 1 to 5 weight percent of said composition.

3. A method according to claim 1 wherein said hydrocarbonaceous fluid ispresent in an amount of from about 1 to 5 weight percent of saidcomposition and is diesel fuel boiling in the range of 325 to 650 F.

4. A method according to claim 1 wherein said hydrocarbonaceous fluid isprimarily paratfinic and is present in an amount of from about 1 to 5weight percent based on said composition, said emulsifier is cationicand res ent in an amount of from about 0.5 to 5 weight percent based onsaid hydrocarbonaceous fluid and the rate of application of saidemulsion to said pneumatic tire face is from about 1 to 15 gallons perhour of use per tire.

5. A method for efliciently compacting and rolling bituminous pavementcompositions at temperatures in excess of 200 E, which comprisescompacting the pavement with a plurality of pneumatic tires whilespraying onto the faces of said pneumatic tires at a sufi'icient rate toprevent adhesion of the bituminous pavement composition to saidpneumatic tires an oil-in-water emulsion comprising from 0.5 to 10weight percent of a primarily paraffinic diesel fuel boiling in therange of about 325 to 650 F. and from 0.1 to 15 weight percent based onthe weight of said diesel fuel a hydrophilic emulsifier and water.

6. A method according to claim 5 wherein said hydrophilic emulsifier isa cationic emulsifier.

7. A method according to claim 5 wherein said diesel fuel is present inamount of from about 1 to 5 weight percent and said hydrophilicemulsifier is an ammonium emulsifier.

References Cited UNITED STATES PATENTS 2,197,183 4/ 1940 Keeler 945O2,978,967 4/1961 MacDonald 94-50 3,162,101 12/1964 Rostler 94-23 FOREIGNPATENTS 923,632 4/1963 Great Britain.

JACOB L. NACKENOFF, Primary Examiner

1. A METHOD FOR EFFICIENTLY COMPACTING AND ROLLING BITUMINOUS PAVEMENTCOMPOSITIONS AT TEMPERATURES IN EXCESS OF 180* F., WHICH COMPRISESCOMPACTING THE PAVEMENT WITH A PLURALITY OF PNEUMATIC TIRES WHILESPRAYING ONTO THE FACES OF SAID PNEUMATIC TIRES AT A SUFFICIENT RATE TOPREVENT ADHESION OF THE BITUMINOUS PAVEMENT COMPOSITION TO SAIDPNEUMATIC TIRES AN OIL-IN-WATER EMULSION COMPRISING FROM 0.5 TO 10WEIGHT PRECENT OF A HYDROCARBONACEOUS FLUID BOILING IN THE RANGE OFABOUT 200*F. TO 1000* F. AND HAVING A VISCOSITY AT 210*F. OF LESS THANABOUT 100 SSU, FROM 0.1 TO 15 WEIGHT PERCENT BASED ON THE WEIGHT OF SAIDHYDROCARBONACEOUS FLUID OF A HYDROPHILIC EMULSIFIER AND WATER.